use crate::{Direction, Entity, FPos, Pos};

pub const ZOMBIE_HEALTH: u32 = 50;

#[derive(Clone, Debug, PartialEq)]
pub enum EnemyMoveSpeed {
	Slow,
	Medium,
	Fast,
}

/// Every (value) seconds, an enemy with a (speed) can move one tile
pub const SLOW_SPEED_SEC_PER_TILE: f32 = 1.;
pub const MEDIUM_SPEED_SEC_PER_TILE: f32 = 0.5;
pub const FAST_SPEED_SEC_PER_TILE: f32 = 0.25;

#[derive(Clone, Debug, PartialEq)]
pub enum EnemyAttackType {
	Melee,
	Ranged,
}

#[derive(Clone, Debug, PartialEq)]
pub enum EnemyType {
	Zombie,
}

#[derive(Clone, Debug, PartialEq)]
pub struct Enemy {
	pub entity: Entity,
	pub enemy_type: EnemyType,
	pub move_speed: EnemyMoveSpeed,
	pub attack_type: EnemyAttackType,
	time_acc: f32,
}

impl Enemy {
	pub fn new(enemy_type: EnemyType, pos: Pos) -> Self {
		match enemy_type {
			EnemyType::Zombie => Self::zombie(pos),
		}
	}

	fn _new(
		pos: Pos,
		health: u32,
		enemy_type: EnemyType,
		move_speed: EnemyMoveSpeed,
		attack_type: EnemyAttackType,
	) -> Self {
		let entity = Entity::enemy(pos, health);
		Self {
			entity,
			enemy_type,
			move_speed,
			attack_type,
			time_acc: 0.,
		}
	}

	fn zombie(pos: Pos) -> Self {
		Self::_new(
			pos,
			ZOMBIE_HEALTH,
			EnemyType::Zombie,
			EnemyMoveSpeed::Slow,
			EnemyAttackType::Melee,
		)
	}

	fn is_there(&self) -> bool {
		self.time_acc
			>= match &self.move_speed {
				EnemyMoveSpeed::Slow => SLOW_SPEED_SEC_PER_TILE,
				EnemyMoveSpeed::Medium => MEDIUM_SPEED_SEC_PER_TILE,
				EnemyMoveSpeed::Fast => FAST_SPEED_SEC_PER_TILE,
			}
	}

	///
	/// Rough concept for enemy "AI":
	///
	/// State: Roam/Patrol
	///     Moves around in a small area (2x2, 3x3, 4x4) randomly choosing direction and how much to move.
	/// State: Attack
	///     Sees player in facing direction (only in box/rectangle in dir)
	///     (ex. facing north, if player is anywhere above monster and theres no walls in the way, attack)
	///     Do A* pathing to player until enemy dead or player dead or floor change
	///
	/// Current implementation below is just a test
	///
	pub fn update(&mut self, player_pos: Pos, time_since_last_frame: f32) {
		if self.entity.pos == player_pos {
			return;
		}

		self.time_acc += time_since_last_frame;
		if self.is_there() {
			let temp_pos = self.entity.pos.step(Direction::West).unwrap();
			self.entity.pos = temp_pos;
			self.entity.fpos = FPos::from_pos(temp_pos);

			self.time_acc = 0.;
		}
	}
}